Update some uses of UTF conversions in chrome/browser to use the base:: namespace.

chrome/browser/storage_monitor/media_storage_util_unittest.cc

Index: chrome/browser/storage_monitor/media_storage_util_unittest.cc
diff --git a/chrome/browser/storage_monitor/media_storage_util_unittest.cc b/chrome/browser/storage_monitor/media_storage_util_unittest.cc
index 20216a1bc5ee8c87653b423dc6c7ebd4827a6629..cc38bd471f4699e25d0f2da575507251c12c1865 100644
--- a/chrome/browser/storage_monitor/media_storage_util_unittest.cc
+++ b/chrome/browser/storage_monitor/media_storage_util_unittest.cc
@@ -140,7 +140,7 @@ TEST_F(MediaStorageUtilTest, DetectDeviceFiltered) {
   event.Wait();
   EXPECT_FALSE(devices.find(kImageCaptureDeviceId) != devices.end());
 
-  ProcessAttach(kImageCaptureDeviceId, ASCIIToUTF16("name"),
+  ProcessAttach(kImageCaptureDeviceId, base::ASCIIToUTF16("name"),
                 FILE_PATH_LITERAL("/location"));
   devices.insert(kImageCaptureDeviceId);
   event.Reset();